1. Field of the Invention
This invention relates to a polymer composite and formed articles thereof. More particularly, the invention relates to a polymer composite which is inexpensive, can be obtained from a short process, and is excellent in flexibility, durability, and injection molding properties. More precisely, the invention relates to an elastomer material useful for rubber contacts.
2. Description of the Prior Art
As elastomers for rubber contacts excellent in flexibility and durability, hitherto, silicone rubber has been known. Resins designed to have same performance as the silicone rubber have been proposed. For example, a composite of polyester and nylon was disclosed in the Japanese Patent Application Laid-Open No. 55054/1985, a composite of thermoplastic polyurethane and nitrile rubber etc. in the Japanese Patent Application Laid-Open No. 207757/1991, a composite of polyolefin and polyurethane in the U.S. Pat. No. 3,969,475, and a composite of thermoplastic resin such as polypropylene and polyurethane in the Japanese Patent Application Laid-Open No. 227459/1990.
However, the silicone rubber, although excellent in flexibility and durability, involves many problems in economy, working efficiency and productivity, such as higher price as compared with general-purpose elastomers, shorter pot life, and long curing time. On the other hand, the polyester composite, nylon composite, and nitrile rubber composite mentioned above are less expensive than the silicone rubber, but possess such demerits as low flexibility and durability, and long processes required for manufacture of the composites. Yet, since one resin component is not sufficiently dispersed in the other resin component, they have problem such as low durability.
The composites disclosed in the U.S. Pat. No. 3,969,475 and the Japanese Patent Application Laid-Open No. 227459/1990 are sufficient in flexibility, but are inferior in repeated bending strength due to insufficient dispersion.
Thus, these composites do not satisfy the requirements for economy, flexibility and durability, especially as the polymer materials for rubber contacts.